Grinding-mill.



No. 847,436. PATENTED MAR. 19, 1907. 0. PFEIFFER. GRINDING MILL.

APPLICATION FILED JAN. 2, 1906.

2 SHEETS-SHEET 1.

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No. 847,436. PATENTED MAR. 19, 1907. 0. PFEIFFBR;

GRINDING MILL.

APPLICATION FILED J ANQZ, 1906- 2 SHEETS-SHEET 2.

Inventor.

OSKAR PFEIFFER, KAISERSLAUTERN, GERMANY.

GRINDING-MILL.

Nth 847,436.

To (all znhlmn if may concern:

Be it known that I, OSKAR PFEIFFE" subject of the'Emperor of Germany, re ding at Kaiserslautern, Rhein falz, Germany, have invented new and usefuFIm specification. My invention relates to improvements in grinding-mills.

In ball and like grinding-mills as heretofore made a number of holes or slits are prothe-sections or steps,

vided in the grinding-plates or races for the outlet of the ground material. This arrangement possesses a number of defects, among wliic may be mentioned the fact that the said holes or slits are partially or wholly hammered together by the balls, so that the;

outlet of the ground material is rendered more or less difficult or is completely pre: vented. Furthermore,- the manufacture of the plates by drilling or casting in the holes or slits presents considerable difliculties, and their durability and strength to resist the continual impact of the ballsis slight.

Now this mvention has for its object to obviate these disadvantages and consists in the im rovements' hereinafter described.

In t e accompanying drawing, Figure 1 is a diagrammatic sectional view of a drum grinding-mill constructed according to the invention. Fig. 2 is an'enlarged view illus trating the outletregulating devices. Fig. 3 is a diagrammatic view of a plant showing my im roved grinding-mill in use therewith.

Fig. 4 1s a sectional view of amodified form of grinding-mill.

a a, are the grinding-plates, which in lieu of being provided with openings or steps, each consisting of a solid iece. The outlets for the ground materia are formed by the spaces these openingsb'eing rovided withadjustable valves or slides c.

ythis means the outlet-openings b can be adjusted to suit the degree of fineness of the ground substance.

The ground material is conveyed from an elevator d, Fig. 3-, down the chute e into the hopper F of a separator. The fine and coarse material are separated in this 'ma' chine, the former passing through the outlet 9 intosacks or the like for transport and the l T coarser materialpassing down the outlet- S pecificationf of Letters Patent. Application filed Januar y z, 190a. ser iu no. 294,297.

, rovements. in Grinding-Mills, of which the f0 lowing is"'a for the outletof the ground materialaremade'in segments .-charge-openingsf between ad adjacentstepped faces of a or openings 6 between I the size thereof,

adapted to lap over said op Patented March 19, 1907.

tube h back into the grinding-mill for further treatment. 1 In this manner the empllpgment'ofthehitherto usual sieves and the for (pbtaming finely-ground material is obviate My invention rnay'be carried out in other forms without departing from the essential feature of the invention, the chief characteristic of which consists in dispensing with the sieve and the like and in the regulation of the degree of fineness by adjusting the area'of the outlet-openings b.

As a modification perforated grindingplates a a, maybe em loyed, (see Fig. 4,) and the openings 1) provi ed in these plates may be more or less closed, as required, by means of the covers 0 c, which are secured to the grinding-plates a, by means of screws 0 c.

Having now: particularly described and ascertained the nature of my said invention and in what manner the same is to be per- ,formed, I declare that what I claim is- I 1. The combination with a grinding-mill having stepped grinding-faces and peri heral discharge-openings, of means for regu lating the size of said openings, whereby said mill may be regulated to directly discharge ground material not exceeding any predetermined size, substantially as described.

2. -The' combination with a grinding-mill having stepped grinding-faces and ieripheral dischar e-openings, of adjustable p ates conpzplilect over said openings,

to said. may be regulated to distructe whereb ,rectly ischarge ground material not exceeding any redetermined size, substantially as described. 3. In a grinding-mill the combination with stepped grinding-faces, having 'acent ends of justable plates adapted to lap over said openings to regulate substantially as described. 4. In a grinding-mill, the combination with stepped grinding-faces having dischar e-openings between the adjacent ends of adjacent stepped faces of sliding plates enings to regulate the size thereof, substantially as described.

. OSKAB PFEIFFER.

Witnesses: I I Y -YPAUL EoDEL'r,

MICHAEL Zrmurn-MANN.

dis- 

